Overlapping Sets

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Overlapping Sets

by okigbo » Thu Nov 19, 2009 5:23 pm
Of the companies surveyed about the skills they req'd in prospective employees, 20% require both computer skills and writing skills. What percent of the companies surveyed required neither C nor W?

1. Of the companies surveyed that req'd computer skills, half req'd writing skills
2. 45% of the companies surveryed req'd writing skills, but not computer skills


What is an efficient approach to working through this problem type?
Source: — Data Sufficiency |

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by ershovici » Fri Nov 20, 2009 1:24 am
Let 100 be the total number of companies
then St.1 - if x is the number of comp that req. comp skills then x/2 req both - not suff.
St.2 45 companies reqired writing skills - not suff.

Combine 45 writing+20both +20 comp + x neither =100
x=15, IMO C

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by okigbo » Fri Nov 20, 2009 9:05 am
Where did you get the 20 for the comp?

What does statement 1 literally mean?

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